Want to export data from multiple similar PostgreSQL tables to one JSON file?
Try Withdata DBToFile, a PostgreSQL to JSON converter for Windows, Linux, and macOS, Export PostgreSQL data to JSON, Easy and Fast.
- Can run in GUI mode, Step by Step, just a few mouse clicks.
- Can run in Command line, for Scheduled Tasks and Streams.
- Support Windows, Linux, and macOS.
Export multiple similar PostgreSQL tables to a single JSON file
Login to PostgreSQL -> Select PostgreSQL tables -> Set JSON file options -> Export PostgreSQL to JSON
Choose PostgreSQL and logon.
Click “Export Similar Tables” at task dialog.
Select JSON file type.
1. Select similar PostgreSQL tables.
2. Set JSON file options.
3. Set rows options.
4. Export multiple similar PostgreSQL tables to a single JSON file.
After exporting, you can view output JSON file.
More about PostgreSQL to JSON converter
Download Withdata DBToFile
See also:
- Export PostgreSQL table to JSON
- Export PostgreSQL query results to JSON
- Batch export PostgreSQL tables to JSON files
PostgreSQL → JSON reference
Type mapping
| Value kind | in PostgreSQL | in JSON |
|---|---|---|
| Int | integer | 1234 (number) |
| Bigint | bigint | 9007199254740993 |
| Decimal | numeric(p,s) | 1234.56 (number) |
| Float | double precision | 1.234e10 (number) |
| Text | varchar(n) | "text" (string) |
| Long text | text | "multi-line\ntext" (escaped newline inside a string) |
| Date | date | "2026-09-18" (string) |
| Datetime | timestamp | "2026-09-18T14:30:00Z" (string) |
| Binary | bytea | "base64:..." (string) |
| Boolean | boolean | true / false (boolean) |
| JSON | jsonb | nested object or array, kept as structure |
Dialect differences
PostgreSQL is a database server and JSON is a file format, so the gap is wider than a dialect difference – the rows below are where values and structure stop lining up.
| Property | in PostgreSQL | in JSON |
|---|---|---|
| port | 5432 | — |
| identifiers | "double quotes" | Double quotes; backslash escapes |
| row limit | LIMIT n | — |
| dates | timestamp, timestamptz, date, time | No date type: dates arrive as strings and the reader must p... |
| long text | TEXT | — |
| binary | BYTEA | Not supported natively - base64 inside a string |
| separator | — | Braces and commas |
| encoding | — | UTF-8 by definition |
| typing | — | string, number, boolean, null, object, array - no date type |
| shape | Tables of rows and columns | Nested objects and arrays |
| ceiling | — | Whole document is usually parsed into memory |
Command line
| Side | Command |
|---|---|
| PostgreSQL | pg_dump or COPY ... TO |
| PostgreSQL (load) | COPY ... FROM |
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